Experimental Characterization of the Shear Properties of 3D–Printed ABS and Polycarbonate Parts

As 3D printing has increased in popularity, it has become more important to understand the properties and characteristics of the parts being produced. The material properties of 3D printed parts are not equivalent to the bulk properties of the materials used to print them. The nature of 3D printing, with varying raster and build orientations, results in anisotropy of the printed parts. This paper presents the experimental techniques and results for the mechanical characterization of acrylonitrile butadiene styrene (ABS) and polycarbonate (PC) 3D printed parts to determine the anisotropy of their shear properties. Because of the anisotropy, tensile material properties cannot be used to determine shear properties. Iosipescu shear specimens were manufactured at various print raster ([+45/−45], [+30/−60], [+15/−75], and [0/90]) and build orientations (flat, on-edge, and up-right) to determine the directional properties of both ABS and PC samples. Ten samples of each raster were subjected to loading in a universal testing machine while making use of 2D digital image correlation (DIC) to measure full-field strain on both sides of the specimen. Results for both the ABS and PC materials show that there were measurable differences in the modulus of rigidity between build orientations and significant differences in shear strength. The ABS samples exhibited strong anisotropy as a function of build orientation while the PC samples exhibited strong anisotropy as a function of raster orientation.